I had a patio that had sunk replaced.
The new patio seems too high- the landscaping was the obvious problem, but now I am concerned because the patio butts against the house and is right up to the siding.
Will this cause problems as water could force its way in and rot out frame?
Is there a standard that should be followed?
Construction code?

Also what is the standard for "pitch"? Water puddles on my new stamped concrete patio?
Shouldn't a pitch cause water to run off?

Welcome Ron:
There was a reason the patio had sunk and it should have been torn out and remedied before the new one was laid.
You may try caulking along the siding to keep the water out. I like to see a patio or porch floor at least 4" below the floor of the house. Your local code may require even more than that.
The standing water is a real problem where you live. It will freeze in the winter and cause your patio to break up. Enjoy it a few years while you save up another project buffer and have the whole thing torn out, subsurface repaired and pour another new one.
Glenn

A patio should slope 1/8" to 1/4" per linear foot away from the house. A 10' patio should slope at least 1.25" to 2.5" away from the house.

Since you have already poured the patio, it good future information.

I would recommend you get in the habit of shoveling your new patio to reduce the effects of standing water/ice that will occur. The thawing/refreezing cycle will not be helpful to the new patio. What is done is done.

As glennjanie writes, it is best to have the patio below the siding since you do not want rainwater backing up to your house and spilling over the top of the foundation or sill plate of your home's framing. Again, what is done is done.

In some cases, the general grading of a lot will force your hand about what you can do. Perhaps this was your case. Anyway, you will need to be attentive to rain/snow issues and try to minimize the effects.